Synthesis and characterization of titanium-containing mesoporous silica by a non-hydrothermal microwave method

We report on a new method for preparing mesoporous silica and titanium-containing mesoporous silica using microwave (MW) synthesis under non-hydrothermal conditions. The materials were characterized by XRD, nitrogen adsorption, UV-vis and FTIR techniques, and compared with a sample prepared by the conventional method. A single peak at 2 theta = 2.4 degrees in the XRD pattern showed the formation of mesoporous silica. A typical isotherm, characteristic of a mesoporous material where pore filling occurred at p/p(o) in the range of 0.2-0.3 was obtained for nitrogen sorption. UV-vis diffused reflectance spectra showed bands at 210-220 nm and a shoulder at 270 nm, indicating the presence of Si-O-Ti bonds for titanium-containing mesoporous silica. This new method has been observed to have inherent advantages over reported methods, such as instant start up, a short heating time and low cost. These mesoporous titanosilicates prepared using a microwave heat energy source are active in the oxidation of 2,6-diisopropylpheno1 (DIPP) and 2,6-di-t-butylphenol (DTBP) with hydrogen peroxide as an oxidant.